This invention relates to aqueous coating compositions and in particular to an aqueous dispersion of an aryloxysulfone copolymer.
Bakeware and cookware require finishes that have food release properties and thermal stability. Also, the exterior surfaces of cookware such as fry pans, covers and fry pans, the sides and bottoms of electric cooking appliances require finishes that are tough, durable and thermally stable. Industrial household ovens require thermally stable scratch-resistant finishes. The coating compositions that form these finishes should be non-airpolluting and preferably should be aqueous solutions or dispersions.
Polysulfone resins are tough, durable, scratch-resistant and thermal stable. These resins are well known in the art as shown by Vogel, U.S. Pat. No. 3,321,449, issued May 23, 1967; D'Allessandro, U.S. Pat. No. 3,355,272, issued Nov. 28, 1967; Cohen et al. U.S. Pat. No. 3,518,235, issued June 30, 1970; Pietrusza et al. U.S. Pat. No. 3,536,665, issued Oct. 27, 1970, and British Pat. No. 1,122,192, published July 31, 1968. However, it has not been possible to formulate these resins into aqueous coating compositions.
According to this invention, it is possible now to prepare coating compositions of an aqueous dispersion of aryloxysulfone copolymer that forms finishes that have excellent adhesion to all types of substrates and have excellent release properties and are tough, durable, and scratch-resistant.